LA 504 FEL Hydraulic Issue...

[gltrap54]

B3200 Kubota LA 504 FEL... Blew a hose to the tilt on bucket & after replacing the hose I no longer have any tilt function... What's the regen procedure for bucket tilt cylinder? What is causing the tilt to lock up in normal hose hook up, swap them & it works fine other than joystick function is backwards....

 

[JWR]

B3200 Kubota LA 504 FEL... Blew a hose to the tilt on bucket & after replacing the hose I no longer have any tilt function... What's the regen procedure for bucket tilt cylinder? What is causing the tilt to lock up in normal hose hook up, swap them & it works fine other than joystick function is backwards....

Not 100% sure I follow your description BUT surely the lines need to be bled completely -- enough so you have just hyd fluid in them and no air. If I understand, you reversed the hoses and it all worked OK but of course the directions were screwed up, right? Surely if you put them back in the right configuration it will clear itself and work then too. Rock the joystick every which way and keep playing with it and it should be OK. There is no need to or procedure for bleeding air -- it just eventually gets run back to the sump and is gone. Otherwise -- you got me baffled.

 

[gltrap54]

Not 100% sure I follow your description BUT surely the lines need to be bled completely -- enough so you have just hyd fluid in them and no air. If I understand, you reversed the hoses and it all worked OK but of course the directions were screwed up, right? Surely if you put them back in the right configuration it will clear itself and work then too. Rock the joystick every which way and keep playing with it and it should be OK. There is no need to or procedure for bleeding air -- it just eventually gets run back to the sump and is gone. Otherwise -- you got me baffled.

Thanks! I've got a 12 year veteran Deere mechanic baffled as well... He spent 2 hours this evening exploring any possible issue and came up empty.... Hate to go to the local dealer where I bought it new because their service department is less than stellar & I can't have my tractor sidelined in their shop for weeks

 

[rScotty]

I wonder if we missed something. The op said that his tractor, "blew a hose". That sounds real specific so I'm assuming that he means the hose ruptured from pressure rather than some other kind of failure.

I've never blown a hydraulic hose. That's a scary thought. Certainly it is not a common thing to have happen - and not something that people expect or worry about. It would take more huge pressure to "blow a hose" & that much pressure is probably going to cause other damage as well.
Normally the relief valves prevent any chance of over-pressure damage.

So what caused the hose to blow? Is that were the problem is?

 

[oldnslo]

Initial thought is the quick disconnect is starting to go bad. They can act like check valves and prevent flow in one direction. On a loader the hose should purge just by cycling the cylinders full travel both directions.

Hoses fail or blow for potentially several different reasons like age, chaffed on something, to tight of bend radius, fatigue from repeated pressure spikes, etc.

 

[gltrap54]

I wonder if we missed something. The op said that his tractor, "blew a hose". That sounds real specific so I'm assuming that he means the hose ruptured from pressure rather than some other kind of failure.

I've never blown a hydraulic hose. That's a scary thought. Certainly it is not a common thing to have happen - and not something that people expect or worry about. It would take more huge pressure to "blow a hose" & that much pressure is probably going to cause other damage as well.
Normally the relief valves prevent any chance of over-pressure damage.

So what caused the hose to blow? Is that were the problem is?

Doing dumb she*t is more than likely the culprit... I was clearing brush & got the bright idea to back drag a sizeable load with the bucket tilted down & that's when the hose went.... Also a great way to bend a cylinder...

 

[gltrap54]

According to my Deere mechanic there is a procedure to regenerate the bucket tilt cylinders either in the valve or the cylinders & he needs that procedure sooo ..... come Monday I'll run by my dealer & plead my case but I wouldn't be at all surprised if they refused to give it to me..... They'll want to take my tractor in the midst of harvest season & keep it several weeks... No can do...

 

[oldnslo]

Regen is typically a function of the control valve and is to cylinders extend faster. If not standard position it would be forth position on dump spool and would have detent just like float for lift lower. Try pushing the joystick farther to the right to see if there is a detent option or if FEL valve is visible look at the end of valve spool oposite where joystick connects. Are the cans or caps covering of spool the same length for both raise/lower and curl dump? If yes you most likely have detent option on both spools. If curl dump is shorter you probably do not have detent option. Either way regen should not be affected by a blown hose.

 

[TGD]

There are no block or lock valves on any of the cylinders so no special procedures are needed. Just connect up the hoses properly, make sure they are connected fully and operate the cylinder several times through it's full range holding for a second or two at full extension and retraction to get any air out.

When you hooked up the hoses backwards, did the cylinder operate in and out through it's full range? If not or you didn't check you could have bent the rod causing it to bind and the relief valve to kick in preventing the rod from moving.

The only hold on a cylinder is the valve block circuit being closed itself. This is one reason why it's generally a bad idea to back drag when not in float as there is no relief to any over pressure other than breaking/bending something or a hose blowing.

 

[gltrap54]

There are no block or lock valves on any of the cylinders so no special procedures are needed. Just connect up the hoses properly, make sure they are connected fully and operate the cylinder several times through it's full range holding for a second or two at full extension and retraction to get any air out.

When you hooked up the hoses backwards, did the cylinder operate in and out through it's full range? If not or you didn't check you could have bent the rod causing it to bind and the relief valve to kick in preventing the rod from moving.

The only hold on a cylinder is the valve block circuit being closed itself. This is one reason why it's generally a bad idea to back drag when not in float as there is no relief to any over pressure other than breaking/bending something or a hose blowing.

Yup we made every effort to get all the air out of the line, even manually bleeding it, so I'm pretty sure that's not the issue.. When we reversed the lines it tilted full range but the joystick operated in reverse of course.... This would indicate I didn't bend anything... As stated, the guy doing the work worked on everything Deere made for 12-15 years & he's left scratching his head...

 

[gltrap54]

Initial thought is the quick disconnect is starting to go bad. They can act like check valves and prevent flow in one direction. On a loader the hose should purge just by cycling the cylinders full travel both directions.

Hoses fail or blow for potentially several different reasons like age, chaffed on something, to tight of bend radius, fatigue from repeated pressure spikes, etc.

You are absolutely correct! Changed the quick disconnects and what do you know, problem solved! I have to wonder if that may have caused the hose to fail?

 

[oldnslo]

Gltrap
Thanks for letting us know what the resolution was and glad you now have a working machine.